70 



pound for pound, represents the least nutritive value of any of the 

 breeds examined. Notwithstanding this fact, the Berkshire heads the 

 list of all in its percentage of nitrogenous substances, and this com- 

 pensates in a large degree for its increased percentage of water. 

 There is quite a satisfactory agreement between the nitrogenous sub- 

 stances in the distribution thereof in the three classes named. The 

 percentage of gelatinoid nitrogenous matters is fairly constant, only 

 in one instance, namely, that of the Yorkshire, rising much above the 

 average. All the other percentages are very near that of the mean. 



In regard to the flesh bases, only one falls considerably below the 

 average, namely, the Duroc Jersey, No. 7, the others being very close 

 to the mean. In total nitrogen there is a marked deficit in the case of 

 the Duroc Jersey, No. 7, but this is due not to the influence of breed 

 alone upon the composition, but to the large excess of fat in the meat 

 of this animal. 



The ash shows a fairly constant number throughout, varying very 

 little from the mean. 



The summation of the analyses is fairly satisfactory. In no case is 

 there as much as 2 per cent unaccounted for, the largest deficit being 

 in the case of the Poland China, where it amounts to 1.55 per cent. 

 When the nature of the material upon which the work was done is 

 considered, the figures are eminently satisfactory. These data afford, 

 it is believed, a better basis for nutritive studies of the meats of pigs 

 than has heretofore been supplied from any chemical laboratory. 



Average of bones. Table 10 contains the average composition of all 

 the bones of each animal. No separate analyses of the bones from each 

 cut were made. For each pig one composite sample was made, includ- 

 ing all the bones of the animal. As is to be expected in a case of this 

 kind, it was found that the composition of the bones is reasonably uni- 

 form in the different animals. In regard to water, the largest quantity 

 was found in the bones of the Poland China, namely, 42.70, and the 

 smallest in the bones of the Duroc Jersey, No. 6, namely, 33.78 per 

 cent. In regard to the content of fat, the largest quantity was found 

 in the bones of the Duroc Jersey, No. 6, namely, 17.64 per cent, and the 

 smallest in the bones of the Poland China, namely, 9.87 per cent. The 

 bones are extremely rich in nitrogenous substances, and these consist 

 mostly of the proteid matter insoluble in hot water. The quantity of 

 gelatinous matter in bones is not so great as would be expected, being 

 but little more, as a rule, than in the meats. On the other hand, the 

 quantity of flesh bases is larger than would be expected, being consider- 

 ably in excess of the quantity of gelatinous matter. The total quantity 

 of nitrogenous matter in the different animals is remarkably near the 

 mean, the mean quantity being 19.95 per cent and the variation not 

 being quite 2 per cent in any case from the mean. The ash, naturally, 

 is very high. The summation of the analyses is not as uniform as could 

 be wished, ranging from 100.90 per cent as the maximum to 95.86 per 



